The leaves indicate a nutrient problem, but that could be from injuries to the trunk/branches (as from the wind), root problems (if roots are overly wet or dry), or disease (root rot, vascular diseases), in addition to simple need for fertilizer.  Can you send picture of the whole plant, and take a close loo at the trunk and stems for injury.  Also, please tell me about the soil - is this a low spot in the yard?  Is is irrigated?  Dry?  
Thanks,
Carrie

Thank you for responding. The trumpet is on the south side and as you see is next to a sprinkler 2x weekly. I am going to have the soil tested but what fertilizer do I use and/or soil amendments ? Help!!

I think this plant may be too wet, possibly temporarily due to recent weather plus irrigation?  Additionally, the spindly growth indicates it may not be getting enough sun.  Datura/Brugmansia can be fertilized with rose/flowering plant fertilizer, using the label directions.  Also check the soil and see if it is wet and if so, try to aim the sprinklers away from the plant.  If you don't see recovery in the next month, there may be a root/crown rot issue, which would require a sample be submitted to a diagnostic lab or at least brought to a county extension office/Master Gardner clinic.